


Sebastian's Birthday

by SmolKittyYura



Category: Kuroshitsuji | Black Butler
Genre: Adult Ciel Phantomhive, Birthday, Birthday Fluff, Birthday Sex, Bottom Ciel Phantomhive, Celebrations, First Time, Fluff and Smut, Gay Sex, M/M, Top Sebastian Michaelis, bon appétit
Language: English
Status: Completed
Published: 2020-04-03
Updated: 2020-04-03
Packaged: 2021-03-01 02:54:40
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,563
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/23464267
Author URL: https://archiveofourown.org/users/SmolKittyYura/pseuds/SmolKittyYura
Summary: It is coming up to a certain anniversary and it's one that Ciel has only ever seen as negative. However, one year he decides to view it a little differently and instead celebrate his meeting with his dear demon, Sebastian Michaelis.
Relationships: Sebastian Michaelis/Ciel Phantomhive
Comments: 3
Kudos: 149





	Sebastian's Birthday

The day seemingly began just like any other day for the Phantomhive butler. He got out of bed. Washed and dressed. Ready to begin cleaning. However, as he walked to the kitchen from his butlers quarters, he noticed everything was already clean. Shining actually. It was very odd indeed and Sebastian was more than confused, but. The demon shrugged it off and went to prepare breakfast for his young Lord. At least he would've shrugged it off if he hadn’t stepped into the kitchen to find it clean, in tact and the food trolley prepared with breakfast. “What on earth is going on?” Sebastian questioned with a raised eyebrow. It was very unusual indeed. It was hard not to wonder if he had entered another dimension by mistake. Regardless, he took hold of the trolley and began to push it towards Ciel Phantomhive’s chambers. It was still a little early, but not worry. The eighteen year old Earl was grumpy and difficult enough in the mornings. A trait the demon put down to his hormones, but then again that didn’t exactly apply to when he first met him eight years ago exactly. “It’s that time of year already. I’ll have to bake him something extra special today.” Sebastian said to himself. On the day every year, he tried to make the day as easy as possible on his master. It was a traumatic anniversary for him and although Ciel hated to be shown comfort or sympathy, even kindness, today was always an exception.

As per usual Ciel had suffered from terrible nightmares, merely hours ago. So when Sebastian entered his chambers to find him wide awake, dressed and working on documents at his desk… The demon for the first time in a long time, was utterly dumbfounded. Something curious was definitely going on today. “My Lord? Have slept?” The butler questioned, choosing to assume he has been up since his nightmare.

The bluenette nodded without taking his voice off his work. “I slept fine. I just decided to get ahead of my work today. On that note, I’d like you to spend today questioning witnesses regarding a horrific string of murders that have been happening of late.” Ciel answered his question simply.

Something was definitely going on. Regardless, it wasn’t for him to question. “Yes, my lord.” Sebastian said with a bow and left with the case documentation Ciel had given him. The murders were truly horrific indeed. The killer had taken to scattering the limbs of their victims across the city of London like a treasure hunt. The demon would be lying if he said he didn’t find their method of choice amusing and of course, he never lied. As any efficient butler would, he made quick work of not only interviewing the witnesses, but he also apprehended the murder and all before dinner. However, he did worry that he’d left his master alone too long. Especially today. No doubt the young Earl would be a shaken, whimpering mess under his blankets by the time he got back.

To his surprise once again, the manor was silent when he returned. Too silent. There was no crashing of dishes or explosions and the place was still clean. Sebastian closed his crimson eyes and listened carefully. He could not hear or sense any distress from Ciel’s direction. At least not from where he was in the foyer. The demon butler decided to investigate and walked towards the drawing room, where he knew the young man was residing.

The second he entered the room, Ciel, Prince Soma, Agni, Lau, Ran-Mao, Elizabeth and the servants, all jumped out. “Surprise!” They all yelled in unison. Naturally Elizabeth was the first one to jump forward and hug the butler. “Happy birthday!” She exclaimed in her usual, cheery tone.

And surprised he was. Never in all his years as a demon has he ever been wished a happy birthday. Hell, he couldn't even remember what day his birthday fell. So he supposed today was a fitting day to choose. The day Ciel Phantomhive called out for him and uttered his new name. Yes. In a way, today was the birthday of Sebastian Michaelis. The butler politely returned Lady Elizabeth's hug. “Thank you. It’s awfully kind of you all to go to so much trouble for me. You really shouldn't ha-“

“Nonsense!” Agni exclaimed as he cut Sebastian off. “After everything you’ve done to help me grow as a kansama and how loyal you are to your master. It is more than worth rewarding and you’ve helped so many here.” The Indian butler insisted, before Prince Soma chirped in, “Agni is right. You might be scary sometimes, but you care and you help people, and work hard.”

The servants all nodded in unison. Sebastian had came to them all when they were at the end of their rope and he offered them a new life, and a home. One they had all grown to love dearly. Not the building, but the beings that resided inside it.

It was then Grell made her presence known and wrapped her arms around Sebastian's arm. “Happy birthday, Bassy! When I heard what the kid was up to, I just had to come and help.” She said in excitement as she hung off him.

Many others in attendance spoke their praises of the unusually perfect butler. Sebastian didn’t know what to make of their words and he didn’t know how to respond. The only person he didn’t hear from was Ciel. Not that it bothered him. The birthday festivities consisted of games and cake, presents. Sebastian got a lot of presents. One from his master being a couple days off. Somehow the demon butler knew the young man wouldn't survive two whole days by himself, so he intended to stay near anyway. Just in case. There was also dancing. Sebastian had been brought to dance with practicality everyone. Even Agni had a dance with his friend. However, the kansama had to quickly tend to his Prince who had, had a little too much to drink and had become extremely clingy towards Earl Phantomhive. The demon chuckled, finding it quite amusing. He couldn't help the fond smile at the young man. It wasn’t hard to work out he was behind all this. The thing he couldn't work out was why.

* * *

Once everyone had given their hugs and said goodbye Ciel made his way upstairs. “Sebastian. Could you follow me?” He requested, before he continued his course.

Sebastian nodded with a soft smile. “Of course, my Lord.” He spoke softly and then followed the Earl to his chambers. In spite of being told he didn’t have to, the butler set to work preparing Ciel for bed. Since he was now an adult, the young Earl often fought Sebastian when he helped him dress. Tonight, he didn’t. Tonight was an exception. As he worked, placing his master's worn clothes on a chair, he thought about the day and something still was nagging at him. Why had he had done it? As soon as he was in his nightshirt, Sebastian gave him a curious look. “Young master, if I may be so bold. Why did you arrange a birthday party for me tonight? The date of my birth is unknown and I am, but a simple butler. Then there is the matter of what took place this day eight years ago. I had thought today the opposite of cause for celebration.” He questioned softly.

Ciel listened to him speak and looked at him with soft, mismatched eyes. It wasn’t hard to work out why Sebastian was so confused, but he had been thinking about it for quite a while. The smaller man scooted over a little on the bed and patted the space in front of him. Once Sebastian was sat on the edge in front of him, he began to speak, “I am more than aware that I don’t know when you were actually born. I am also very aware of what took place this day. However, this day marked the end of that agonizingly terrible month. This month. While it’s true I may never completely recover from the trauma of it all. I have realized that I have been looking this day anyway, all wrong. Yes, I lost so much, but I gained you. It was the day I summoned you and gave you, your name. So in a way, it was the day of your birth. Your birth as Sebastian Michaelis. My butler, demon and the only man whom I trust. Once I realized that, today didn’t seem so bad. I wanted to celebrate the day I gained the person closest to me. I wanted to celebrate you and thank you for all you do and have done for me. Happy birthday, darling demon.”

Sebastian was at a loss for words as he took in every one that left his master's soft pink lips. For the umpteenth time that day, he was surprised and he felt genuinely touched. He was feeling something. A fondness and affection for the young Earl. A deep care for him. Something that felt a little different. A little more than what should be felt between a servant and master. With the thought of his mater’s lips in mind, the demon dared to lean in and he pressed a light kiss to the lips in question. It was just how he had imagined it would be. The scolding he had expected to get for such an action never came and instead, Ciel kissed him back.

After a few moments the pair pulled apart and Ciel was sporting a small blush. Neither said anything at first and then the Earl got off the bed, to grab something out of the closet. Sebastian watched with a raised eyebrow as the bluenette hid something behind his back and climbed onto his lap. Not that he minded it. His master just kept surprising him. When Ciel revealed it was a Funtom kitten plush behind his back, his eyes softened. “Happy birthday, Sebastian.” Ciel said again and handed the demon the little toy. The plush cat was black with white sock paws and crimson eyes. It was clear who the inspiration for the gift was.

Sebastian took it with a smile. “Thank you.” He said and held the stuffed kitten close for a moment, before he gave his master a kiss on the cheek.

“It was nothing.” Ciel insisted with a small blush that earned him a chuckle from the demon. In turn he geared at him. The Funtom cat plush was a one of a kind. There had never been one made like it before and there never would be. The only one in existence would now always belong to Sebastian Michaelis. Just like there would only ever be one Sebastian Michaelis in existence. To Ciel at least. The man’s lap whom he sat on was the only being that mattered to him and would ever need.

He watched as the demon admired the small cat toy. It baffled him why he was so obsessed with the little fur balls. Ciel’s mismatched eyes locked onto Sebastian's lips. The same lips that were on his own not that long ago and he wanted to feel then again. So while Sebastian's attention was on his gift, Ciel leaned in and softly kissed his soft lips.

Sebastian was indeed surprised once again, but he kissed him back gladly and set the cat aside on the nightstand. The demon’s arms wrapped around the young man’s slim waist as Ciel deepened the kiss. It appeared his master was quite eager tonight. Not something he had a problem with. The butler stood with Ciel in his arms, only to gently lay him on his back. Sebastian completely covered his frail body, without leaving his lips for a second. When the bluenette parted his lips, the demon butler took the invitation and slipped his tongue in his mouth. Damn did he always taste good. The thought of anyone else tasting his sweetness, even Lady Elizabeth, caused a small growl to vibrate in the demon’s throat. This earned Sebastian a pleasant shiver from the smaller man. Which in turn he took as permission to break the kiss, only so he could claim his master's deliciously beautiful neck.

Ciel gladly allowed his demon to claim and mark his skin. His lips felt so good against his neck. A definite sweet spot and one of his most sensitive sweet spots at that, and Sebastian knew that fact all too well. The Earl sang out little moans and other noises, the deeper the love bites became. Since he had turned eighteen, their servant and master relationship remained just that. In public anyway. Behind closed doors they had taken to make out sessions and some fooling around, but they had never gone all the way. Tonight, Ciel planned to give himself completely to his demon. So while Sebastian was preoccupied devouring his neck and claiming every inch of it. The bluenette unbuttoned his tailcoat, followed by his waistcoat and his white shirt. He removed the black tie next and pushed off all three layers at once.

Sebastian chuckled when he finally noticed his young Lord undressing him so eagerly. He decided to humor him and helped him slide off his top layers, before he helped the smaller man remove his own top garments. Only so he could mark up the rest of his upper body. However, he stopped himself. Any time they got so intimate, Sebastian would always put on the breaks at a certain point. This was to force himself to hold back. Of course he wanted to take Ciel, but he was more than aware of his partner's past trauma and he did not wish to add to it or cause him a panicked episode. He got enough of those at night while he slept.

When Sebastian stopped, Ciel let out an unsatisfied whine. He knew exactly why his butler did that and as much as he appreciated it. It wasn’t something the demon had to do. “You can continue. Please, don’t stop.” Ciel requested, sounding dangerously like he was begging. “I’m ready and I want you to be the person I give myself to. I don’t count anything that happened that day. That cult doesn’t own me. I don’t give a fuck about what the brand mark says. I’m yours.” The Earl assured as he looked up into his crimson eyes.

Sebastian listened to him and a grin tugged at the corner of his mouth. He adored that in spite of the mark on his body, he refused to accept the cult as the one’s to take his virginity. It was bold and even though it didn’t work that way, he was happy to be the one that got to show Ciel a different way. He got to show him love, tenderness and that his body was treasured to him. Not some toy to be sacrificed at a later date. “Alright. On one condition. Tell me if you need me to stop. If I detect even a hint of panic in your eyes, we’re stopping.” Sebastian said sternly, making it clear it was non negotiable.

Ciel listened to him and nodded. “That sounds perfectly reasonable. If it gets too much or I feel like I’m going to panic, I will tell you.” He agreed as he took hold of Sebastian's gloved contract hand.

The demon brought the Earl’s hand that claimed his own to his lips and tenderly kissed the back of it. Then he let go and stood up, running a hand through his sleek black hair. The action earned him another shiver from his master. Sebastian smirked at the response and with his eyes locked on Ciel’s sapphire and amethyst eyes, he pulled his right glove off with his teeth. He did so purposely slow, knowing how much his partner loved when he did so, but the slowness was to tease him a little. Once it was off, he discarded the glove to the floor and repeated his action with the left glove.

Ciel’s breath hitched as he watched him remove his gloves so seductively. Sebastian had definitely caught him staring when he did it for other things. The dragging on of it drove the impatient noble insane though. His self control was crumbling by the minute and once their contract seal was visible on Sebastian's left hand, his restraint was gone. Ciel sat up and pulled Sebastian closer to him by the button of his trousers, only to pull it off with surprising and obviously untapped strength. The Earl then grabbed the zip in his teeth and pulled it down.

His partner's impatient actions surprised the demon and he chuckled softly. He watched as Ciel pulled his zipper down with his teeth and it took all of his willpower not to take him then, and there.

Ciel pulled his demon out of his underwear, before he pulled back the skin of the tip and took it in his mouth. The low moan he heard from Sebastian's lips was music to the Earl’s ears. So he dipped his tongue in the slit, before he took his hardening length further in his mouth. To Ciel he tasted better than any of his beloved sweets and the look of absolute bliss on the demon butler's face, was so satisfying for him to see. Even as Sebastian buried a hand in his hair, he didn’t pull and he was gentle in spite of his pleasure.

His master's mouth was so wet and warm, it felt so could around him. He of course held back the urge to thrust into the sensation. There’d be plenty of time for that later. Sebastian let out a deep moan as he felt Ciel’s tongue in the slit of his tip, when he bobbed his head up, a definite sweet spot of the demon’s. After only a few minutes, Sebastian was already at his limit. His partner knew what he was doing and he didn’t hold back. “My Lord… If y-you keep going, I’m going to-“ He couldn't even finish his sentence as he was already cumming in his beloved's mouth.

Ciel was ready for it and swallowed it all down. He was glad he got to make his demon feel so good and he was excited for what was to come. He looked up at Sebastian with his mismatched eyes and his lips sported a small grin of satisfaction. As well as a bead of cum on the corner of his mouth.

Sebastian leaned down and gently held his chin in his hand, before he licked the cum from his mouth. The butler could already see his master's own arousal tented in his trousers. His lips rose in a devilish smile as he picked the older man up, to lay him more comfortably on the bed, with the pillows under his delicate mortal head. Once his Lord was comfortable, he completely removed his trousers and underwear to comply with the begging look in sapphire and amethyst eyes. “Just because you’re the Queen’s guard dog, doesn’t mean you have to beg like one.” Sebastian mused as he got on the bed and knelt at his Lord’s feet.

Ciel sat up on his elbows and narrowed his eyes playfully at the demon. “Cheeky.” He retorted and watched as Sebastian leaned in close to his erect crotch. The Earl’s breath hitched in anticipation and he groaned when he nuzzled his face against his erection.

“My, my, my. You got this excited from just pleasuring me. How very sinful of you, my Lord.” Sebastian teased as he undid Ciel’s trousers, pulling them down. He tossed them to the floor with the rest of their clothes and instructed, “On your hands and knees, my love.”

The young Earl nodded and did as he was told. He got on his hands and knees, with his butt raised to his partner. Sebastian licked his lips at the sight, but before he did anything, he asked, “I will ask you this once. Are you sure about this?” The enthusiastic nod he received was permission enough and he couldn't help chuckling at his beloved's adorable enthusiasm. Although, he knew better than to tell his prickly master that. With his answer, Sebastian in close to to Ciel’s puckered and pink hole. He licked his tongue over it and earned himself pleasant him from the Earl. “Bon appétit.” The demon whispered, before his tongue slowly entered the bluenette.

The array of beautiful sounds the demon got from his prey were like the most precious melody to his ears. Sebastian pushed his tongue deeper into Ciel, dragging more moans out of him. His master's taste and voice alone could excite him. When the Earl had loosened up enough, Sebastian added a finger and pushed it deep in him, alongside his tongue. If he was going to enter the smaller male, he was going to properly prepare him. There was no room for error with such an intimate act. He was after all, one hell of a demon lover.

Ciel did appreciate the tender care Sebastian took to prepare him and as much as he loved how his fingers, and tongue felt inside him, he wanted his partner inside him. “Sebastiannn…” He whined with a pleading look in his eyes as he looked back at his demon.

The Phantomhive butler for what had to be the first time in his long demons life, except when faced with a cat, blushed. He blushed from his master's tone and the look in his mismatched eyes. Sebastian had to take a deep inhale of breath as he sat up and licked his lips. He had already been painfully hard for a while and his tip was dripping with pre-cum, but Ciel was his only priority. The demon gently laid the Earl on his back and leaned down to tenderly kiss his lips as he lifted his hips, so he could position himself at his beloved master's entrance. Sebastian slipped his tongue through Ciel’s parted lips as he deepened the kiss to distract him, slowly pushing his length inside him.

A low moan came from Ciel’s throat when he he felt Sebastian enter his tight, wet and begging hole. The combination of the demon’s delicious taste and the feeling of being completely filled with his cock when he bottomed out, was absolute ecstasy. A high he had never known before. The bluenette more than appreciated that his lover waited for him to adjust. Sapphire and amethyst eyes stared up into crimson in awe. A look and side of the Earl no one else got to see. His heart was filled with love for the man connected to him and he couldn't think of anyone better to give himself to.

Sebastian stared into his master's eyes and admired the evidence of their bond on his right eye. “Forgive me for saying this, if it displeases you, young master, but… I love you, Ciel Phantomhive.” The demon confessed with a small blush.

Ciel’s own cheeks reddened as he heard him and his eyes widened, before softening on his vulnerable looking demon. “I love you too, Sebastian Michaelis. It doesn’t displease me at all.” He returned, hoping to reassure him and then he said softly, “You can move. Thank you for waiting.”

The demon butler looked dumbfounded by his Lord’s response and replied, “There is no need to thank me, darling. If I couldn't take my time and treasure my secret lover’s body, what kind of demon butler lover would I be?” He mused and then slowly began to draw out of Ciel to his tip, before he gently thrusted back in.

“I-Idiot.” Ciel retorted through a breathy moan in response to use of one of that line of Sebastian's.

“You love it.” Sebastian whispered as he smirked.

The Earl wrapped his arms around the demon’s neck. “I love y-you.” He moaned, before he pulled his partner's head down for a passionate kiss.

Sebastian returned in a low growl, “And I love you, darling.” The raven haired demon picked up his pace a little and aimed his cock so that it hit Ciel’s prostate with every thrust. This earned him the most beautiful sound from the young man beneath him he had ever heard from his luscious lips. The mewls Ciel gave out was nothing short of a kitten like sound and Sebastian adored it. He kept up his pace and it was long until Ciel came hard onto his stomach. However, the demon wasn’t done.

Ciel panted heavily from the intensity of his orgasm. His mismatched eyes were hazy and he was utterly blissed out from the high of it. He looked up at Sebastian and could tell from the look in his eyes, that he desired to continue. So before he could ask, the Phantomhive Earl murmured, “You can keep going until you are satisfied. It is your present after all.”

Sebastian adored the look on his master's face and nodded with a soft smile. He softly brushed some hair out of Ciel’s eyes and kissed him softly as he started to thrust into his sweet hole. The demon emitted his own moans of pleasure as he felt Ciel’s walls suck him in. After minutes more of trusting against his love’s sweet spot and his insides clenching around his length, he came deep inside him.

The young Lord easily came again and covered himself in his cum. The feeling of being filled with his demon’s release of pleasure, made him feel happier than he thought it would.

The demon butler felt just as high from his orgasm. His young master felt better than any woman and no woman could even begin to compare to his beauty. He leaned down and lapped up Ciel’s cum, not leaving a drop to go to waste. “Thank you for the birthday meal, darling~" He thanked with a grin, before he pulled out of his beloved Lord and got up from the bed. He grabbed his shirt and pulled it on, before a hand reached out to tug at the end of the white fabric. “My Lord?” He asked curiously as he looked at his exhausted human.

“Stay.. Please.” Ciel requested, sounding dangerously like a plea. As his master, he knew that Sebastian likely had work to tend to. However, as his lover and partner, he didn’t want him to go after they had been so intimate.

Sebastian smiled softly, leaned down and took the hand that held his shirt as he kissed the back of it. “Of course, my darling.” He agreed and got in next to Ciel, before pulling him close. He kissed the top of his soft blue head that rested on his chest and cuddled him tightly.

Ciel immediately relaxed in his embrace and had a content smile on his face. Something that no one else had ever seen. “Happy birthday, Sebastian.” He murmured, before he drifted off into a peaceful and nightmare free sleep.

The demon smiled softly and the contentment on his master's face as he gently kissed the end of his nose. “It has been a happy birthday indeed, darling.” He whispered back and closed his eyes, choosing to rest with his beloved in his arms.


End file.
